.TH std::basic_ios::eof 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::basic_ios::eof \- std::basic_ios::eof

.SH Synopsis
   bool eof() const;

   Returns true if the associated stream has reached end-of-file. Specifically, returns
   true if eofbit is set in rdstate().

   See ios_base::iostate for the list of conditions that set eofbit.

.SH Parameters

   \fI(none)\fP

.SH Return value

   true if an end-of-file has occurred, false otherwise.

.SH Notes

   This function only reports the stream state as set by the most recent I/O operation;
   it does not examine the associated data source. For example, if the most recent I/O
   was a get() which returned the last byte of a file, eof() returns false. The next
   get() fails to read anything and sets the eofbit. Only then does eof() return true.

   In typical usage, input stream processing stops on any error. eof() and fail() can
   then be used to distinguish between different error conditions.

.SH Example


// Run this code

 #include <cstdlib>
 #include <fstream>
 #include <iostream>

 int main()
 {
     std::ifstream file("test.txt");
     if (!file) // operator! is used here
     {
         std::cout << "File opening failed\\n";
         return EXIT_FAILURE;
     }

     // typical C++ I/O loop uses the return value of the I/O function
     // as the loop controlling condition, operator bool() is used here
     for (int n; file >> n;)
        std::cout << n << ' ';
     std::cout << '\\n';

     if (file.bad())
         std::cout << "I/O error while reading\\n";
     else if (file.eof())
         std::cout << "End of file reached successfully\\n";
     else if (file.fail())
         std::cout << "Non-integer data encountered\\n";
 }

.SH See also

   The following table shows the value of basic_ios accessors (good(), fail(), etc.)
   for all possible combinations of ios_base::iostate flags:

        ios_base::iostate flags basic_ios accessors
        eofbit  failbit  badbit good() fail() bad() eof() operator bool operator!
        false   false    false  true   false  false false true          false
        false   false    true   false  true   true  false false         true
        false   true     false  false  true   false false false         true
        false   true     true   false  true   true  false false         true
        true    false    false  false  false  false true  true          false
        true    false    true   false  true   true  true  false         true
        true    true     false  false  true   false true  false         true
        true    true     true   false  true   true  true  false         true

   feof checks for the end-of-file
        \fI(function)\fP
